Selve N, Wegner A
J Mol Biol. 1986 Feb 20;187(4):627-31. doi: 10.1016/0022-2836(86)90341-4.
Actin filaments capped at the barbed ends were formed by polymerizing monomeric actin onto a gelsolin-actin complex. The rate of depolymerization and polymerization of the pointed ends was determined by diluting gelsolin-capped actin filaments into various concentrations of monomeric actin. Under the conditions of the experiments (100 mM-KCl, 2 mM-MgCl2 at 37 degrees C) the rate constant of dissociation of subunits both from a shortening and a lengthening filament was found to be 0.21 s-1. As the rate of dissociation of subunits from the slow pointed end determines the rate of treadmilling, it is concluded that actin filaments treadmill with a rate of about 2 micron/h.
通过将单体肌动蛋白聚合到凝溶胶蛋白 - 肌动蛋白复合物上，形成了在带刺末端被封端的肌动蛋白丝。通过将凝溶胶蛋白封端的肌动蛋白丝稀释到不同浓度的单体肌动蛋白中，来测定肌动蛋白丝钝端的解聚和聚合速率。在实验条件下（37℃时100 mM - KCl，2 mM - MgCl2），发现亚基从缩短和延长的肌动蛋白丝上解离的速率常数均为0.21 s-1。由于亚基从缓慢的钝端解离的速率决定了肌动蛋白丝的踏车运动速率，因此可以得出结论，肌动蛋白丝以约2微米/小时的速率进行踏车运动。
